The Mid-Atlantic Bight (MAB) is a well-studied region of the U.S. East coast continental margin, rich in submarine canyons. Baltimore and Norfolk canyons were studied during the multidisciplinary Atlantic Deepwater Canyons project through funding from BOEM, NOAA and USGS. Benthic infaunal community structure, standing stock, species richness and diversity was assessed in the context of canyon environmental parameters and ecosystem ecology. Relating the prevailing canyon environmental parameters to the benthic infauna communities of Baltimore and Norfolk canyons allows for investigations of important factors underpinning canyon ecosystem ecology and eco-functioning of MAB canyons. Benthic infaunal samples were collected by NIOZ box corer in 2012 and 2013 along canyon axes and comparative adjacent slopes, at standardised depths. Fauna were identified to lowest taxonomic unit or assigned putative species and comprised over 400 taxa, the majority represented by polychaetes. The observed nepheloid layer in Baltimore Canyon corresponded to major shifts in infaunal community structure, potentially promoting an enrichment paradox i.e. where increased organic matter delivery creates a heightened sediment oxygen demand, leading to changes in community structure. Significant community shifts were observed in stations at depths > 900m in Baltimore Canyon, coinciding with higher organic matter levels in depths below the nepheloid layer. In contrast, slope communities showed a more uniform infaunal assemblage where distinct zonation patterns by depth were observed. Preliminary data for Norfolk Canyon also show clear differences between canyon and slope benthic communities. Sediment dynamics, organic inputs and disturbance events are clear factors in determining benthic infaunal diversity and standing stock dynamics in and around these canyons.